An update - got the lens from Simon as per my previous link.
25 deg looks very good - the throw is similar to SMO (well, may be just a tiny-tiny bit less), but the diffused hot spot is way nicer indoors and in close ranges. Also it produce a nice “ambient” spill at very wide angles.

Note, that the lens are 1 mil less in diameter than the tube, hence they will not necessary be centred. Since my lens didn’t come with any white holder, I improvised by cutting a stripe of 200gsm paper about 4mm wide, folding as a ring and putting it just behind the glass - it helped the TIR to center.